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Entwicklung von Lösungsvorschlägen, einschließlich rechtlicher Instrumente, zur Verbesserung der Datenlage beim Verbleib von Altfahrzeugen

Jährlich werden in Deutschland rund 8 Millionen Personenkraftwagen (Pkw) außer Betrieb gesetzt, von denen rund 3 Millionen als endgültig außer Betrieb gesetzt betrachtet wurden. Aus den verfügba-ren statistischen Quellen ließ sich der Verbleib von jährlich gut 1 Million der endgültig außer Betrieb gesetzten Pkw in Deutschland nicht belegen. Gegenstand des Forschungsvorhabens war die mög-lichst weitgehende Schließung dieser ąstatistischen Lückeĺ. Hierfür wurden der Status Quo sowie die Ursachen der statistischen Lücke intensiv über Expertengespräche, Workshops, Primärerhebungen, Datenbankauswertungen und Literaturrecherchen analysiert und die Verbleibswege in Szenarien systematisiert. Im Ergebnis zeigte sich, dass die Anzahl der zugrunde gelegten Außerbetriebsetzungen erhöht werden musste, da N1-Fahrzeuge bisher nicht erfasst wurden (0,36 Mio. Fz.). Die korrigierte Berechnung der Anzahl endgültig außer Betrieb gesetzter Fahrzeuge ergab eine Minderung der Lücke um 0,52 Mio. Fahrzeuge. Lücken im Informationsfluss ausländischer Zollausgangsstellen waren die Ursache für eine Lücke von rund 0,21 Mio. Fahrzeugen. Vor dem Hintergrund dieser und der weiteren Ergebnisse konnte die statistische Lücke weitestgehend geschlossen werden. Datenunsicherheiten bestehen insbesondere bei den Verbleibswegen der nicht-anerkannten Demontage im In- und Ausland. Die Studie entwickelt unter Berücksichtigung der aufgezeigten Ursachen der statistischen Lücke Empfehlungen und Maßnahmenvorschläge zur Optimierung der Situation. Die zukünftige Verbesse-rung der Datenlage soll mit Maßnahmen auf zwei Ebenen erreicht werden: Maßnahmen zur Verbesserung der Statistiken und Informationsflüsse, Maßnahmen zur Steuerung der Fahrzeuge in besser dokumentierte Verbleibswege. Hierzu gehören beispielsweise die Stärkung des Vollzugs gegen nicht anerkannte Demontage, die Verbesserung der Abgrenzung zwischen Altfahrzeug und Gebrauchtwagen sowie die Stärkung des Verwertungsnachweises. Quelle: Forschungsbericht

B 2.3: Transport of agrochemicals in a watershed in Northern Thailand - Phase 3

Das Projekt "B 2.3: Transport of agrochemicals in a watershed in Northern Thailand - Phase 3" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre, Fachgebiet Biogeophysik durchgeführt. Land use changes of the last decades in the mountainous regions of Northern Thailand have been accompanied by an increased input of agrochemicals, which might be transferred to rivers by surface and/or subsurface flow. Where the river water is used for household consumption, irrigation and other purposes, agrochemical losses pose a serious risk to the environment and food safety. In the first and the second phase, subproject B2 collected data on and gained knowledge of the vertical and lateral transport processes that govern the environmental fate of selected agrochemicals at the plot and the hillslope scale (Ciglasch et al., 2005; Kahl et al., 2006). In the third phase, B2.3 will turn from the hillslope to the watershed scale. For simulation of water flow and pesticide transport the SWAT model (Neitsch et al., 2002b) will be adapted and used. The study area will be the Mae Sa watershed (138 km2), which includes the Mae Sa Noi subcatchment where B2 carried out detailed investigations during the last two phases. The specific focus of the subproject will be the parameterization and calibration of the SWAT model and its integration into the model network of the SFB. The SFB database has been established and can be used for model parameterization. In addition, high-quality geo-data are available from the Geoinformatic and Space Technology Development Agency (GISTDA) in Chiang Mai. For model calibration, discharge measurements are available for the Mae Sa Noi subcatchment (12 km2) and for the neighboring Mae Nai subcatchment (18 km2). To collect data on the Mae Sa watershed discharge, at the very beginning of the third phase gauging stations will be established in a midstream position and at the outlet of the watershed. Pesticide fluxes will be measured at each gauging station as well as in the Mae Sa Noi subcatchment, where B2.2 has operated two flumes equipped with automatic discharge-proportional water samplers since 2004. Rainfall distribution and intensity will be monitored with a net of automatic rain gauges. Hydrograph separation will be performed using soil and river temperatures (Kobayashi et al., 1999). Within the watershed temperature loggers will be installed at different soil depths to measure the temperature of the different discharge components. Already at the beginning of the second year of the third phase we will start to couple the SWAT model with land use and farm household models of the SFB and to use the model to assess the effect of land use and land management changes on the loss of pesticides to surface waters.

B 5.1: Fate of agrochemicals in integrated farming systems in Son-La province, Northern Vietnam

Das Projekt "B 5.1: Fate of agrochemicals in integrated farming systems in Son-La province, Northern Vietnam" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre, Fachgebiet Biogeophysik durchgeführt. In Son La province, Northern Vietnam, many irrigated farming systems include ponds in which small-scale farmers raise fish to produce additional food and income. The main field crops in this area are paddy rice and maize. Often, irrigation water is first used in paddy fields, before it flows to the fishponds. Because farmers regularly apply considerable amounts of agrochemicals, mainly insecticides, to field crops fish production suffers. Moreover, agrochemicals may enter the human food chain. Subproject B5.1 will study the fate of agrochemicals applied in two subcatchments near Yen Chau, Son La province. Investigations will be carried out in close collaboration with A1.3, B4.1, C4.1, D5.2, and G1.2. In the two subcatchments, fishponds have been investigated by D5.1 since 2003. We will carry out a survey of the subcatchments with special emphasis on the water distribution systems (fields, ponds, canals, brooks). The data will be linked to the GIS (Geographical Information System) set up by B4.1. In one subcatchment, B5.1 will install a weather station as well as five TDR (time do-main reflectometry) probes and tensiometers. Water flow through the system will be recorded by means of water meters and V-shaped (Thompson) weirs equipped with automatic pressure sensors. Soil and water samples from selected fields sites, pond inflows, and ponds will be regularly screened for agrochemicals using the procedure developed by B2.1 (Ciglasch et al., 2005; see below). Soil and sediment characteristics that determine water regime and soil-agrochemical interaction, e.g. texture, organic carbon content, hydraulic conductivity, partitioning coefficients, and half-life times will be measured in laboratory and field experiments in cooperation with B4.1. In preparation for the next phase, discharge will be assessed and agrochemical concentrations monitored in the main catchment.

B 2: Lateral water flow and transport of agrochemicals - Phase 1

Das Projekt "B 2: Lateral water flow and transport of agrochemicals - Phase 1" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre durchgeführt. The project aims at developing a model of the dynamics of agrochemicals (fertilisers, pesticides) and selected heavy metals on a regional scale as a function of cropping intensity in the highland areas of Northern Thailand. The model shall predict the effects of cropping intensity on mobility and leaching of agrochemicals in the agriculturally used system itself but also on the chemical status of neighbouring ecosystems including downstream areas. The methods for measuring and estimating the fluxes of agrochemicals in soils will be adapted to the conditions of the soils and sites in Northern Thailand. Fluxes of agrochemicals will be measured in fruit tree orchards on the experimental sites established together with projects B1, C1 and D1. Also, processes governing the dynamics of agrochemicals will be studied. The objectives for the first phase are as follows: - To identify suitable study sites - To establish the methods for measuring the fluxes of agrochemicals in the study sites - To adopt the analytical procedures for pesticides - To identify and parametrise the processes governing the mobility of agrochemicals - To identify the major chemical transformation processes for agrochemicals in the soils of the project area - To establish models of the fate of agrochemicals an the plot scale. Dynamics of agrochemicals include processes of mobilisation/immobilisation, degradation and transport. Both, experiments and field inventories are needed to elucidate the complex interaction of the various processes. Field measurements of the fluxes of nutrient elements (N, P, K, Ca, Mg, Mn, Zn, Cu), pesticides and some heavy metals will be conducted at different regional scales (plot, agricultural system, small catchment, region). Laboratory and field experiments consider chemical, physicochemical and biological processes. Biological processes and degradation of pesticides will not be considered in the first phase of the project, however, they should be included later on. The project as a whole is broken down into three essential parts, which consecutively follow each other. The subproject is methods- and processes-orientated. Methods, which were developed in Hohenheim to quantify the fluxes of chemicals in soils have to be adapted to meet the requirements of the specific conditions in the study area. Recently, these methods are already under development in tropical environments (Vietnam, Costa Rica). After adaptation the methods will be used to yield flux data on the plot scale. These data are needed to help deciding which of the hypothesised processes are of major importance for modelling the dynamics of agrochemicals. The final outcome of this project phase are models of the fate of agrochemicals as a function of management intensity on the plot scale.

Plant-soil interactions in changing rice cropping systems and their influence on C and N dynamics

Das Projekt "Plant-soil interactions in changing rice cropping systems and their influence on C and N dynamics" wird vom Umweltbundesamt gefördert und von Universität Bonn, Institut für Nutzpflanzenwissenschaften und Ressourcenschutz - Pflanzenernährung (Prof. Werner) durchgeführt. Plant-soil interactions drive the input, cycling and losses of C and N in soil. This subproject aims at elucidating the input and fate of C in the soil-plant systems and its effect of N retention in soil under different paddy management (continuous vs. alternating with maize cropping). In particular we will investigate (i) how much of the assimilate C is released by the plants into the rhizosphere soil, and how this rhizodeposition is affected by N supply, soil density and crop variety during plant development, (ii) how the exudation of C and N responds to land use change, (iii) how C released into the rhizosphere affects the turnover of soil C and utilization of fertilizer N, and (iv) to what degree leaching contributes to the loss of C and N from the rooted surface soil. To answer these questions, we will combine the use of isotopic 13C and 15N labeling in laboratory and field experiments with a sophisticated characterization of root exudates, root border cells, and compound-specific isotope tracing in the residues of bacteria and fungi in rhizosphere, bulk soil as well as within different dissolved organic and inorganic carbon species in soil leachates. In this way and in collaboration with SP 2, 5, 6, and 7 of this research unit, our project links the cycling of C and N in paddy soils to one of its most prominent drivers, the release of organic compounds by roots.

Teilprojekt 1

Das Projekt "Teilprojekt 1" wird vom Umweltbundesamt gefördert und von Isodetect GmbH durchgeführt. Fate-PFT zielt auf neuartige Schadstoff-Monitoringverfahren bei der Sanierung kontaminierter Standorte. Durch die Analyse stabiler Isotope, diagnostischer Komponentenverhältnisse und von Transformationsprodukten können der natürliche oder chemisch induzierte Abbau sowie die Herkunft per- und polyfluorierter Alkylsubstanzen (PFAS) in Wasserkompartimenten ermittelt werden. Dringend notwendige In-situ-Sanierungskonzepte lassen sich mit diesem Wissen entscheidend verbessern, denn sie erhalten eine neue Informationsbasis zur Planung sowie Erfolgskontrolle von kosten- und energieeffizienten Maßnahmen. Das Ziel von Fate-PFT ist die Etablierung innovativer Verfahren für die Kohlenstoff- und Schwefelisotopenanalyse von PFAS sowie die Ermittlung von diagnostischen Komponenten-verhältnissen und Transformationsprodukten. Für diese neuen Messtechniken werden geeignete Extraktions- und Derivatisierungsmethoden entwickelt und deren Anwendbarkeit an Umweltproben gezeigt. In Laborversuchen werden Bezugswerte für die verlässliche Interpretation von Felddaten (d. h. Isotopenwerte, Transformationsprodukte, diagnostische Komponenten-verhältnisse) ermittelt. Die Analyseverfahren werden in einem leistungsstarken Methodenpaket gekoppelt, um das Schicksal (engl. fate) von PFAS an kontaminierten Standorten fundiert bewerten zu können. Darüber hinaus sollen die Erkenntnisse der Laborversuche als Grundlage für die Etablierung von Machbarkeitsstudien bzw. Vortests zu standortspezifischen PFAS-Sanierungsverfahren genutzt werden. Fate-PFT trägt wesentlich zur Verbesserung des Leistungsspektrums der Isodetect GmbH bei. Dieses wird um wichtige, marktrelevante Applikationen erweitert, welche die Wettbewerbsfähigkeit des Unternehmens als europäischer Marktführer für die Quellen- und Abbaubewertung von Umweltchemikalien stärken.

Origin and fate of dissolved organic matter in the subsoil

Das Projekt "Origin and fate of dissolved organic matter in the subsoil" wird vom Umweltbundesamt gefördert und von Leibniz Universität Hannover, Institut für Bodenkunde durchgeführt. Dissolved organic matter (DOM) is one major source of subsoil organic matter (OM). P5 aims at quantifying the impact of DOM input, transport, and transformation to the OC storage in the subsoil environment. The central hypotheses of this proposal are that in matric soil the increasing 14C age of organic carbon (OC) with soil depth is due to a cascade effect, thus, leading to old OC in young subsoil, whereas within preferential flowpaths sorptive stabilization is weak, and young and bioa-vailable DOM is translocated to the subsoil at high quantities. These hypotheses will be tested by a combination of DOC flux measurements with the comparative analysis of the composition and the turnover of DOM and mineral-associated OM. The work programme utilizes a DOM monitoring at the Grinderwald subsoil observatory, supplemented by defined experiments under field and labora-tory conditions, and laboratory DOM leaching experiments on soils of regional variability. A central aspect of the experiments is the link of a 13C-leaf litter labelling experiment to the 14C age of DOM and OM. With that P5 contributes to the grand goal of the research unit and addresses the general hypotheses that subsoil OM largely consists of displaced and old OM from overlying horizons, the sorption capacity of DOM and the pool size of mineral-associated OM are controlled by interaction with minerals, and that preferential flowpaths represent 'hot spots' of high substrate availability.

Teilprojekt 2

Das Projekt "Teilprojekt 2" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum für Umweltforschung GmbH - UFZ, Department Isotopenbiogeochemie durchgeführt. Das Ziel von Fate-PFT ist die Entwicklung innovativer Methoden für die Charakterisierung und Quantifizierung von Abbauprozessen per- und polyfluorierter Alkylsubstanzen (PFAS). Dabei ist die Etablierung einer Multi-Element-Isotopenanalyse von PFAS ein wesentlicher Bestandteil. Begleitend dazu werden innovative Extraktions- und Derivatisierungsmethoden entwickelt. Neben der Abbaubewertung von PFAS ist die Schadstoffquellidentifizierung ein zentraler Bestandteil des Projektes. Hierfür wird der isotopische Fingerabdruck von PFAS-Komponenten bestimmt. Parallel dazu werden Analysemethoden zur Bestimmung diagnostischer Komponentenverhältnisse von PFAS-Komponenten für die Herkunftserkundung etabliert. Des Weiteren werden in Laborversuchen Bezugswerte für PFAS-Eliminations- und Abbauprozesse ermittelt, die für die Interpretation von Felddaten benötigt werden. Neben Isotopenfraktionierungsfaktoren und diagnostischen Komponentenverhältnissen werden dabei auch Transformationsprodukte identifiziert, deren Detektion einen aktiven Schadstoffabbau anzeigt. Abschließend werden die entwickelten Methoden an Proben von Feldstandorten getestet, um Schlüsselparameter zur Erkundung und Sanierung von PFAS-kontaminierten Standorten zu definieren.

Effects of biochar amendment on plant growth, microbial communities and biochar decomposition in agricultural soils

Das Projekt "Effects of biochar amendment on plant growth, microbial communities and biochar decomposition in agricultural soils" wird vom Umweltbundesamt gefördert und von Forschungsinstitut für biologischen Landbau Deutschland e.V. durchgeführt. Biochar has a great potential to ameliorate arable soils, especially those that are low in organic matter due to intensive use or erosion. Biochar is carbonised organic material with high porosity that brings about changes in physical, chemical and biological soil functions. Biochar amended soils show a higher water and cation exchange capacity with reduced leaching and enhanced availability of plant nutrients. The microbial biomass in biochar amended soils is enhanced and more diverse. Biochar is stabilised organic material, which is likely to remain for hundreds of years in the soil. Photosynthetically fixed atmospheric CO2 stabilised in biochar may thus act as a direct carbon sink and help to mitigate climate change. As feedstock and production conditions produce different biochar qualities predictions of effects in soil need to consider biochar and soil properties case by case. To date biochar has been approved to ameliorate highly weathered tropical soils with positive effects on crop growth and yield. Distinct microbial groups were reported to be enhanced in soils but if this depends on the particular soil or biochar or a combination of both is an open question, especially in temperate climates. Likewise, it is not known if microorganisms colonising biochar surfaces are responsible for its mineralization or if they just use the new niches provided. The aim of the proposed project is to investigate the influence of two biochar types on soil-plant systems by determining i) soil nutrient availability, plant growth and nutrient uptake, ii) structure and function of soil microbial communities, iv) the decomposition and fate of biochar in soils. We will use two loessial soils from the well-known DOK-trial with different soil organic matter content. Other soils from the region will be selected to provide a wider range of soil quality, in particular pH. The biochars will be produced by pyrolysis and hydrothermal carbonization (HTC) from the C4-plant Miscanthus gigantea. Pyrolysis derived material has bigger pore sizes due to the evaporating gasses and is commonly alkaline, whereas the HTC derived biochar has a finer pore size, a much higher oxygen content and more acidic functional groups.

Dynamic (redox) interfaces in soil - Carbon turnover in microbial biomass and flux into soil organic matter

Das Projekt "Dynamic (redox) interfaces in soil - Carbon turnover in microbial biomass and flux into soil organic matter" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum für Umweltforschung GmbH - UFZ, Department Umweltbiotechnologie durchgeführt. Existing models of soil organic matter (SOM) formation consider plant material as the main source of SOM. Recent results from nuclear magnetic resonance analyses of SOM and from own incubation studies, however, show that microbial residues also contribute to a large extent to SOM formation. Scanning electron microscopy showed that the soil mineral sur-faces are covered by numerous small patchy fragments (100 - 500 nm) deriving from microbial cell wall residues. We will study the formation and fate of these patchy fragments as continuously produced interfaces in artificial soil systems (quartz, montmorillonite, iron oxides, bacteria and carbon sources). We will quantify the relative contributions of different types of soil organisms to patchy fragment formation and elucidate the effect of redox con-ditions and iron mineralogy on the formation and turnover of patchy fragments. The develop-ment of patchy fragments during pedogenesis will be followed by studying soil samples from a chronosequence in the forefield of the retreating Damma glacier. We will characterize chemical and physical properties of the patchy fragments by nanothermal analysis and microscale condensation experiments in an environmental scanning electron microscope. The results will help understanding the processes at and characteristics of biogeochemical interfaces.

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